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问题 单项选择题

下列关于供热系统与设备的检测内容，哪一项是错误的

A．散热器在安装之前应做水压试验，试验压力如无设计要求时应为工作压力的1.5倍，但不小于0.6MPa
B．散热器背面与墙内表面距离的安装允许偏差为3mm
C．低温热水地板辐射采暖敷设的盘管埋地部分采用接头时，在盘管隐蔽前必须进行水压试验，且应保证试验压力满足要求
D．使用塑料管的热水采暖系统安装完毕，在管道保温前应进行水压试验，应以系统顶点工作压力加0.2MPa作水压试验，同时在系统顶点的试验压力不小于0.4MPa

答案

参考答案：C

解析： 根据《建筑给水排水及采暖工程施工质量验收规范》GB 50242—2002第8.3.1条，选项A正确；根据第8.3.7条，选项B正确；根据第8.5.1条，选项C错误，不应有接头；根据第8.6.1-3条，选项D正确。

选择题

设NA表示阿伏加德罗常数的值，下列叙述不正确的是[ ]

A．标准状况下，11.2L三氯甲烷所分子数为0.5NA

B．常温常压下，1mol甲基（-CH3）所含电子数为9NA

C．常温常压下，22g氧气和26g臭氧混合后，混合气体所含氧原子总数为3NA

D．标准状况下，将22.4L的NO2通入足量水中发生反应，转移的电子总数为2/3NA

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单项选择题

Ban the Band

Every year, our school has a dance for all the students. It’s a little funny seeing friends in clean shoes and trousers or colorful (1) , instead of the usual school uniform.

Most of us think the dance is great (2) even the teachers enjoy being there. (3) , two weeks ago someone said that there would be no (4) band this year— only CDs. "I don’t (5) it!" Amy cried out during the lunch break.

"Someone said the school couldn’t (6) a band, and they think it’s too noisy anyway, "added Daniel.

"Well, I don’t think it’s (7) enough without a band!" declared Angela, "and I’m going to see what can be done. "

Angela was as good as her (8) . In the afternoon she went to see the school headmaster who agreed to give the (9) some more thought. And he suggested that one (10) for having a band was to increase the price of each ticket from MYM5 to MYM10. Angela had to (11) out whether the students would like to do that."I need all of you to help me, " she (12) to our group before school the next day. "Mr. Berry gave me a list of all the names, and suggested we ask each one their (13) about the band and the extra cost. " (14) the day we asked around as Angela suggested, and wrote down people’s feelings about the band and the cost. We were amazed how much (15) there was for the band and everyone agreed to pay the extra MYMS."I’m surprised, " smiled Mr. Berry, when we gave him the (16) . "I really thought that only a few people (17) their band and that the cost would be too high. OK. Angela, your next (18) is to find a good band and line them up for the dance. "Angela was all smiles and (19) the news to Amy and Daniel. "You’re (20) , " smiled Daniel to Angela as he thought how close they came to having a less than perfect dance.

14（）

A.On 

B.For 

C.By 

D.During
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